Alasdair Wilkins in io9 (image by Tonis Pan):

There's an idea that suggests all the universe's electrons are actually one particle forever traveling backwards and forwards in time. It's a simple, elegant idea that solves some of physics's biggest mysteries. There's only one tiny problem. It's complete nonsense.

This is the story of that bizarre thought experiment and John Archibald Wheeler, the brilliant, largely unsung physicist who came up with it.

Like so much of the quantum world, electrons are strange. What's worse, they're all strange in exactly the same way. Every electron is identical to every other electron. They all have the same mass, the same electric charge, and the same spin. (For more on what these terms mean, check out our field guides here and here.) Electrons are just one of the indistinguishable particles – other examples include photons, neutrinos, protons, neutrons, and indeed most of the subatomic particles.

This isn't a trivial point, either. Not only is it impossible to tell electrons apart based on their physical properties, it's essentially impossible to tell them apart at all. This is because determining specific electrons by their position would require measuring their trajectories with exact precision, and the laws of quantum mechanics forbid this. Between measurements, electrons in the quantum world are probabilistic, defined by wave functions that give the odds of finding that particle in any given position. When the wave functions of multiple electrons overlap, it becomes officially impossible to determine which of the electrons was the one that was originally measured.

An interview with Tim Maudlin in The Atlantic (photo by Ross Anderson):

Your group has identified the central goal of the philosophy of cosmology to be the pursuit of outstanding conceptual problems at the foundations of cosmology. As you see it, what are the most striking of those problems?

Maudlin: So, I guess I would divide that into two classes. There are foundational problems and interpretational problems in physics, generally –say, in quantum theory, or in space-time theory, or in trying to come up with a quantum theory of gravity– that people will worry about even if they're not doing what you would call the philosophy of cosmology. But sometimes those problems manifest themselves in striking ways when you look at them on a cosmological scale. So some of this is just a different window on what we would think of as foundational problems in physics, generally.

Then there are problems that are fairly specific to cosmology. Standard cosmology, or what was considered standard cosmology twenty years ago, led people to the conclude that the universe that we see around us began in a big bang, or put another way, in some very hot, very dense state. And if you think about the characteristics of that state, in order to explain the evolution of the universe, that state had to be a very low entropy state, and there's a line of thought that says that anything that is very low entropy is in some sense very improbable or unlikely. And if you carry that line of thought forward, you then say “Well gee, you're telling me the universe began in some extremely unlikely or improbable state” and you wonder is there any explanation for that. Is there any principle that you can use to account for the big bang state?

Amartya Sen in the FT:

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Like many board games that were developed in India, of which chess is perhaps the most important and famous, the game of “snakes and ladders” too emerged in this country a long time ago. With its balancing of snakes that pull you down and ladders that take you up, this game has been used again and again as a metaphor for life, telling us about our fortunes and misfortunes, and going further, about the consequences of good deeds and bad actions. Good decisions yield handsome rewards – taking us rapidly up a ladder – and bad moves yield severe penalties – making us suffer a precipitate decline through the mouth of a long snake, all the way down to its distant tail.

Britain too found in this board game from their colony a good way of expressing their traditional ethical tales, illustrating, for example, the simple moralistic world of what was called “Virtue Rewarded and Vice Punished” – a game that became very popular in early 19th century. The English version used the graphic illustrations of the snakes and ladders to depict traditional English moral tales that made this old Indian game popular first in England and then in the British-dominated global world of the nineteenth century. The Indian names – from Sanskrit, Hindi, Urdu and other subcontinental languages – for the qualities that respectively yielded rewards and punishment were replaced in the English version into the names of classical English virtues such as penitence, pity, obedience and self-denial yielding ascent up the ladders, while time-honoured vices of depravity, cruelty, dandyness made one slip rapidly down through the body of a snake.

The diagnosis of virtues and vices is, of course, adaptable, and the richness of the analogy of snakes and ladders can be put to use today in discussing modern problems as well – even the contemporary challenges of economic and social policies. We can well ask: what are the nasty snakes we face today in thinking about economic policies in our troubled world, and what helpful ladders we should try to climb up in moving an economy and society forward – in a world full of opportunities as well as serious dangers. The distinctions are quite important for the emerging economies which are trying to decide where to emerge. We do not want to emanate from the bottom end of snakes, and would rather emerge at the top of elevating ladders. How can we do this?

Christa Wolf belonged to the generation in which I also count myself. We were stamped by National Socialism and the late—too late—realization of all the crimes committed by Germans in the span of just twelve years. Ever since, the act of writing has demanded interpreting the traces that remain. One of Christa Wolf’s books, Patterns of Childhood, responds to that imperative, exposing her successive immersions in brown-shirted dictatorship and the doctrines of Stalinism. False paths credulously followed, stirrings of doubt and resistance to authoritarian constraints and beyond that, the recognition of one’s own participation in a system that was crushing the utopian ideals of Socialism—those are hallmarks of the five-decades of writing that established Wolf’s reputation, a journey that leads book by book from The Divided Sky (1963) to her final work, Stadt der Engel (“City of Angels,” 2010); and the books remain. To pick one out: “What Remains” is the title of a story published in June 1990 by Aufbau Verlag in the East and Luchterhand Verlag in the West. Even before it was available to East and West German readers, some West German journalists—the sort who assumed they were history’s victors and the hour of reckoning was at hand—ignored the embargo and struck. Christa Wolf, the celebrated author who had been much-praised for her resistance, the 1980 recipient of the Büchner Prize, Germany’s most prestigeous literary award, who was mobbed by enthusiastic students two years later as she delivered her Frankfurt Lectures on Poetics, Christa Wolf, whose voice had been heard in both Germanies, was now—the Wall hardly having fallen—subjected to an unending barrage of words.

more from Günter Grass at the NYRB here.

Among the 457 letters in Joseph Roth: A Life in Letters, there is not one love letter. This may not surprise fans of the writer — author of The Radetzky March, The Emperor’s Tomb, and Job, among others — who may know Joseph Roth as a vagabond and misanthrope whose occupation as a journalist had him traveling from one European country to the next, living in rented rooms, wearing threadbare clothes, without a bank account, mostly alone, too miserable for romance, the consummate Wandering Jew. But even Roth the World War I soldier left no love letters, no tender requests to, perhaps, a girl he left behind in the crumbling Hapsburg Empire, asking for solace or maybe a photo. Nor did he write any romantic epistles to the lovers with whom he found companionship and comfort in his final years. There are a handful letters from Roth’s pre-war younger days, but they are all written to his cousins in Lemberg. They are letters of encouragement, advice, pontifications, the kind of letters one writes in youth that are more an affirmation of one’s self-understanding: “I am a sworn enemy to etiquette,” he wrote to his cousin Resia (which, in any case, was not true) and “…just like in Goethe’s Faust, which, alas and alack, you haven’t read.” “Who ever would have guessed it: all of nineteen!” he wrote to his younger cousin Paula when he was 22. “But then nineteen years are like a piece of fluff on the scales of eternity. And it’s in eternity that we live. From eternity, in eternity, for eternity. Yes, for eternity as well.”

more from Stefany Anne Golberg at The Smart Set here.

A new species of book has emerged to tell us about the financial panic and subsequent economic calamity that have befallen the United States (and much of the rest of the world). Some books zero in on a particularly dramatic episode like the spine-tingling final hours leading up to the decision to let Lehman Brothers go under. Others recount the rise or fall of some venerable banking house such as Goldman Sachs or Merrill Lynch and treat these commercial ups and downs as if they were the sagas of grand empires come and gone. Biographical variants gives us the inside dope on titans of finance, invariably men of obsidian hearts and egomaniacal will, undone by their global ambition. Yet another sub-species of this genre, of which Jeff Madrick’s Age of Greed is an example, tries to combine story-telling and profiles of the rich and infamous with a survey and analysis of the whole sorry landscape of financial wilding and how its debaucheries came to be. Melodrama and moral drama supply the oxygen for this new literature. So we have books called Age of Greed, The Greed Merchants, The Big Con, Zombie Capitalism, The Great American Stick-Up, Bad Money, The End of Wall Street, The Banksters, Griftopia. Most of these books share a story line about what happened. An excess of greed nurtured in the highest precincts of the country’s financial establishment and ignored, deliberately or negligently, by those public authorities charged with monitoring and reining in these out-sized appetites, led inexorably to the near terminal breakdown, whose after-shocks reverberate to this day.

more from Steve Fraser at Dissent here.

From Salon:

When it came to his work, J.D. Salinger was the ultimate control freak. He strove for absolute perfection in his writing and sought complete power over its presentation. He ordered his photo be removed from the dust jacket of “The Catcher in the Rye,” fought with numerous publishers over his book’s content and presentation, and his disdain for editing was legendary. When a copy editor at the New Yorker dared to remove a single comma from one of his stories, Salinger snapped. “There was hell to pay,” recalled William Maxwell, and the comma was quickly reinstated. Recently uncovered letters demonstrate how the author repeatedly refused any film adaptation of his classic novel. He felt no actor could properly fill the role of Holden Caulfield, although he quipped to Ernest Hemingway that he might be persuaded to play the part himself. In a way, Salinger is still exerting similar control over our ability to define his legacy two years after his death on Jan. 27, 2010 – and he is using his writings to maintain that control. The difficulty in defining Salinger’s legacy stems from his decades of seclusion after his last publication in 1965 and the stubborn hope of millions that he continued to write for the next 45 years.

From Scientific American:

As a dung beetle rolls its planet of poop along the ground it periodically stops, climbs onto the ball and does a little dance. Why? It's probably getting its bearings. A series of experiments published in the January 18 issue of PLoS ONE shows that the beetles are much more likely to perform their dance when they wander off course or encounter an obstacle. Until now, no one had any idea what a jitterbugging dung beetle was up to. Emily Baird of Lund University in Sweden and her colleagues study how animals with tiny brains—such as bees and beetles—perform complex mental tasks, like navigating the world. The dung beetle intrigues Baird because it manages to roll its dung ball in a perfectly straight line, even though it pushes the ball with its back legs, its head pointed at the ground in the opposite direction. If the six-legged Sisyphus can't see where it's going, how does it stay on its course?

Every now and then, a dung beetle stops rolling, mounts its ball and pirouettes. Baird noticed that dung beetles do not dance as often in the lab, where they roll around on flat surfaces, as they do in the field, where the terrain is rough and rocks and clumps of grass often obstruct the beetles' paths. She guessed that by climbing onto a ball of dung four or five times its height, a beetle gets a pretty good vantage point from which to correct any navigational mistakes.

More here.

Farhad Manjoo in Slate:

Jonathan Weisman in the New York Times:

“I think it is an important moment in the Capitol,” said Representative Zoe Lofgren, Democrat of California and an important opponent of the legislation. “Too often, legislation is about competing business interests. This is way beyond that. This is individual citizens rising up.”

It appeared by Wednesday evening that Congress would follow Bank of America, Netflix and Verizon as the latest institution to change course in the face of a netizen revolt.

Legislation that just weeks ago had overwhelming bipartisan support and had provoked little scrutiny generated a grass-roots coalition on the left and the right. Wikipedia made its English-language content unavailable, replaced with a warning: “Right now, the U.S. Congress is considering legislation that could fatally damage the free and open Internet.” Visitors to Reddit found the site offline in protest. Google’s home page was scarred by a black swatch that covered the search engine’s label.

Phone calls and e-mail messages poured in to Congressional offices against the Stop Online Piracy Act in the House and the Protect I.P. Act in the Senate. One by one, prominent backers of the bills dropped off.

More here.

What does a bill like PIPA/SOPA mean to our shareable world? At the TED offices, Clay Shirky delivers a proper manifesto — a call to defend our freedom to create, discuss, link and share, rather than passively consume.

From Lifehacker:

The Stop Online Piracy Act (SOPA) and the Protect IP Act (PIPA) are two bills that sound like they have a mildly positive aim but, in reality, have serious potential to negatively change the internet as we know it. While the Obama administration has come out against SOPA, effectively shelving it indefinitely, the very similar PIPA bill is still alive and well. Both SOPA and PIPA put power in the hands of the entertainment industry to censor sites that allegedly “engage in, enable or facilitate” copyright infringement. This language is vague enough to target sites you use every day, like Facebook and Google, making these bills a serious problem. Here's what you need to know about the bills and what you can do about them.

The idea behind these bills sounds reasonable. They came about in order to try and snuff out piracy online, as the entertainment industry is obviously not excited that many people are downloading their products without payment or permission. The issue is, however, that it doesn't really matter whether you're in support of piracy, against it, or just don't care. The methods are ineffective. Here's what they are and why they're problematic.

More here.

For those outside the US, as well an within, a petition from citizens of the world, over at Avaaz:

For years, the US has condemned countries like China and Iran for their clampdown on Internet use. But now, the impact of these new censorship laws could be far worse — effectively blocking sites to every Internet user across the globe.

Last year, a similar Internet censorship bill was killed before reaching the US Senate floor, but it's now back in a different form. Copyright laws already exist and are enforced by courts. But this new law goes much further — granting the US government and big corporations enormous powers to force service providers and search engines to block websites based just on allegations of violations — without a trial or being found guilty of any crime!

Free speech advocates have already raised the alarm, and some key senators are trying to gather enough support to stop this dangerous bill. We have no time to lose. Let's stand with them to ensure that American lawmakers preserve the right to a free and open Internet as an essential way for people around the world to exchange ideas, share communication and work collectively to build the world we want. Sign the petition to stop censorship, and save the Internet as we know it.

Sign the petition!

Jon Brodkin in Ars Technica:

As Ars readers know, Wikipedia, reddit, Craiglist, and others are blacking out their sites today in protest of the Stop Online Piracy Act (SOPA) and Protect IP Act (PIPA), antipiracy bills that protestors believe would give far too much power to rightsholders at the expense of the Internet as a whole.

Members of Congress are already backpedaling on some of the provisions in SOPA and PIPA, and Rep. Darrell Issa (R-CA) said Tuesday that he expects to have more co-sponsors for his alternative (and much saner) OPEN Act “than SOPA has in the House.”

SOPA opponents say it is critical to block the bill now, because if it is turned into law, website owners will be at risk of having payments blocked, or forced into lengthy and expensive litigation even if they're not trying to enable piracy or profit from it.

“Scribd could not have come into existence in a world governed by SOPA,” said Scribd co-founder Jared Friedman during a conference call yesterday. Alexis Ohanian, co-founder of reddit (which shares a parent company with Ars Technica), said much the same thing about Internet entrepreneurs. “I'd hate to be the Congressperson who has to go back to his or her district and say, 'You know what, maybe this is not the industry for you. Maybe you can try your luck in Canada.'”

Video hosting site Veoh found out the hard way what litigation can do to an Internet business, even when the law is on your side. Veoh was “litigated to death” before being finally cleared in a lawsuit filed against the site by Universal Music Group. “The lawsuit dramatically impacted our company,” said founder Dmitry Shapiro. “It cost us millions of dollars to litigate. It took up a tremendous amount of executives' time. More importantly, it dramatically demotivated our 120 employees who were constantly concerned about what this meant and what would happen to them and their families.”

While 3QD is not blacking out our content (we believe it is better for us to stay on and bring attention to the problem), we are in full support of the anti-SOPA strikes and protests happening all over the internet today.

Ezra Klein in the Washington Post:

As an example of political mobilization —and a new form of political mobilization at that — the anti-SOPA campaign is likely to enter the organizing textbooks. Saul Alinsky could never have seen this coming. As an example of the power and prevalence that these Web sites have in our lives, the anti-SOPA blackouts are a bit unsettling. SOPA might be a particularly noxious piece of legislation, but the future will bring bills that Internet giants don’t like, yet might actually be good for consumers. Will they be able to resist mobilizing against those, too? Still, as an example of the creativity that shines across the Internet, the anti-SOPA protests are, well, sort of awesome. Here are five of the best:

1) Wired.com, where the homepage is redacted, at least until you mouse over the content;

2) Wikipedia.com, where you get to see the article you want for a flash, but are quickly pushed to an ominous, black page with an explanation of the protest and a tool for contacting your representative;

3) Greenpeace.org, where the Internet has gone dark and your mouse acts as a spotlight;

4) Mashable.com, where the front page looks almost normal, but the content is all about SOPA, including ‘This is the Internet After SOPA [PICS]”;

5) Google.com, where they’ve blacked-out the Google logo in a way that sustains the site’s basic functionality—so they’re not misusing their power too much— but makes their point very, very clear.

More here. And here is a good primer on the issues. And please see the post before this one and sign the anti-SOPA petition there.

From Google:

Two bills before Congress, known as the Protect IP Act (PIPA) in the Senate and the Stop Online Piracy Act (SOPA) in the House, would censor the Web and impose harmful regulations on American business. Millions of Internet users and entrepreneurs already oppose SOPA and PIPA.

Millions of Americans oppose SOPA and PIPA because these bills would censor the Internet and slow economic growth in the U.S.

The Senate will begin voting on January 24th. Please let them know how you feel. Sign this petition urging Congress to vote NO on PIPA and SOPA before it is too late.

Go here now to sign the petition. Read more about SOPA and PIPA here.

From The Guardian:

A calligrapher worked for five years to create the world's biggest Qur'an in a bid to show the world that Afghanistan's rich cultural heritage and traditions have been damaged but not destroyed by 30 years of war, it has been revealed. The lavish book, with pages measuring 2.28 metres by 1.55 metres, has been certified as the world's largest by the Afghan ministry of Haj and religious affairs, according to the Kabul cultural centre that houses it. The previous claim to the title was for a copy unveiled last year in Russia's Tatarstan region. The Afghan Qur'an weighs 500kg and its 218 pages of cloth and paper, bound inside an embossed leather cover made from the skins of 21 goats, cost over £300,000 to create.

Mohammad Sabir Khedri, the master calligrapher behind the project, worked with nine students on a design that combines gold script with millions of tiny colourful dots, forming highly symbolic decorations around the giant pages. “I wanted to use as many tasteful colours as possible to make this holy book look beautiful,” he said, standing beside his enormous creation in a room built specially to house it. Khedri not only created the masterpiece, he managed to keep it a secret for over two years. It was finished in 2009, but the binding and room to house it were not ready until the start of 2012, when it was finally unveiled. The Qur'an is housed in a cultural centre originally founded in the 1980s, and once home to 50,000 books, a medical centre, and schools for Afghan crafts such as carpet weaving.

More here.